What can be said about the 89/10 gear vs. 87/10 with regards to gear play and noise level?

I will say I have never been a Hirobo fan, I have had every size Trex and a Vibe 50 and lots of others in between but I got a good deal on an SDX from a guy who one it at IRCHA and I have to say this Helicopter flys better than anything I have ever flown. Its easy to work on and tracks so well it almost flys itself. No joke here I am now a Hirobo fan for life and will not even think of getting rid of it. Anyone who tries this helicopter will own one, it makes life so easy in that there are no upgrades needed and if you are learning it is so easy to fly or if you are real good it just does what you tell it to do with no hesitation. Worth every penny !!